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101.
Enmin Song Dongshan Huang Guangzhi Ma Chih-Cheng Hung 《Expert systems with applications》2011,38(6):6720-6726
Semi-supervised learning has attracted much attention in pattern recognition and machine learning. Most semi-supervised learning algorithms are proposed for binary classification, and then extended to multi-class cases by using approaches such as one-against-the-rest. In this work, we propose a semi-supervised learning method by using the multi-class boosting, which can directly classify the multi-class data and achieve high classification accuracy by exploiting the unlabeled data. There are two distinct features in our proposed semi-supervised learning approach: (1) handling multi-class cases directly without reducing them to multiple two-class problems, and (2) the classification accuracy of each base classifier requiring only at least 1/K or better than 1/K (K is the number of classes). Experimental results show that the proposed method is effective based on the testing of 21 UCI benchmark data sets. 相似文献
102.
The crossed cube, which is a variation of the hypercube, possesses some properties that are superior to those of the hypercube.
In this paper, we show that with the assumption of each node incident with at least two fault-free links, an n-dimensional crossed cube with up to 2n−5 link faults can embed, with dilation one, fault-free cycles of lengths ranging from 4 to 2
n
. The assumption is meaningful, for its occurrence probability is very close to 1, and the result is optimal with respect
to the number of link faults tolerated. Consequently, it is very probable that algorithms executable on rings of lengths ranging
from 4 to 2
n
can be applied to an n-dimensional crossed cube with up to 2n−5 link faults.
相似文献
Gen-Huey ChenEmail: |
103.
Change of Hygienic Quality and Freshness in Tuna Treated with Electrolyzed Water and Carbon Monoxide Gas during Refrigerated and Frozen Storage 总被引:4,自引:0,他引:4
Yu-Ru Huang Chyuan-Yuan Shiau Yen-Con Hung Deng-Fwu Hwang 《Journal of food science》2006,71(4):M127-M133
ABSTRACT: Among different fish slices used for sashimi preparation, tuna is the most popular and preferable fish type for Taiwanese people. To improve the hygienic quality of fish slices, electrolyzed (EO) water containing 10, 50, and 100 mg/L chlorine, was used in combination with CO gas treatment. Effect of different treatment on aerobic plate count (APC), volatile basic nitrogen (VBN), K value, and Hunter L*, a*, b* values of yellow-fin tuna steak during storage (4 °C and −20 °C) were evaluated. It was found that APC, VBN, and K values increased with storage time for all treatment. Except for K value, APC and VBN of tuna steak treated with the combination of more than 50 mg/L chlorine EO water and CO gas had the lowest value after 8 d of refrigerated storage. Hunter a* value of tuna steak treated with only CO gas was the highest, followed by those treated with EO water and CO gas. These results demonstrated that EO water containing 50 mg/L chlorine combined with CO gas treatment in tuna fish steak would be an effective method for enhancing the hygienic quality and freshness for tuna meat and extending refrigerated storage time. Tuna treated with EO water containing 100 mg/L chlorine and CO gas combination had the lowest APC immediately after treatment and reduced further to below detection limit after 1 mo frozen storage at −20 °C. 相似文献
104.
In this study, a new oxygen-deficient cathode material, Sm0.5Sr0.5Co1−xCuxO3−δ (SSCCu) was developed. It is expected to enhance the efficiency of intermediate-temperature solid oxide fuel cells (IT-SOFCs). The structure, conductivity and electrochemical performance of SSCCu were examined as a function of copper content. The structure of Sm0.5Sr0.5Co0.9Cu0.1O3−δ and Sm0.5Sr0.5Co0.8Cu0.2O3−δ samples was a single orthorhombic perovskite phase. Second phase SrCoO2.8, however, formed in the Sm0.5Sr0.5Co0.7Cu0.3O3−δ and Sm0.5Sr0.5Co0.6Cu0.4O3−δ samples. The conductivity of the Sm0.5Sr0.5Co0.7Cu0.3O3−δ cathode was higher than that of other samples. However, the Sm0.5Sr0.5Co0.8Cu0.2O3−δ electrode exhibited the lowest overpotential of 25 mV at 400 mA cm−2 and the lowest area special resistance of 0.2 Ω cm2 at 700 °C. 相似文献
105.
The kinetics of reactions of ternary systems based on bisphenol A diglycidyl ether, bisphenol A, and a sulfanilamide curing agent were investigated using HPLC, during two different synthesis paths. The influence of tetrabutylphosphonium tetrafluoroborate as a catalyst for the epoxy–phenol reaction was studied. For the same initial composition, polymers differing by the crosslink point distribution and the chain length between crosslinks were synthesized. Different solid‐state behavior is expected in these two categories of networks. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 580–591, 2001 相似文献
106.
MPEG-b-PMCL and MPEG-b-PBCL diblock copolymers were synthesized by ring-opening polymerization of 4-methyl-?-caprolactone (MCL) or 4-phenyl-?-caprolactone (BCL) using monomethoxy poly(ethylene glycol) (MPEG, Mn = 550 or 2000 g mol−1) as the macroinitiator and SnOct2 as the catalyst. These copolymers were characterized by differential scanning calorimetry (DSC), 1H NMR, 13C NMR, and gel permeation chromatography. The thermal properties (Tg and Tm) of the diblock copolymers depend on the composition of polymers. When larger amount of MCL or BCL was incorporated into the macromolecular backbone there was an increase in Tg. Their micellar characteristics in the aqueous phase were investigated by fluorescence spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). The block copolymers formed micelles in the aqueous phase with critical micelle concentrations (CMCs) in the range of 0.5-2.9 mg L−1, depending on the composition of polymers. The lengths of hydrophilic segment influence the shape of micelle. The mean hydrodynamic diameters of micelles from DLS were in the range of 70-140 nm. The drug entrapment efficiency and the drug-loading content of micelles depending on the composition of block polymers were described. 相似文献
107.
Facile fabrication of polyethylene/silver nanoparticle nanocomposites with silver nanoparticles traps and holds early antibacterial effect 下载免费PDF全文
Dau Hung Anh Kanchana Dumri Nguyen Tuan Anh Winita Punyodom Pornchai Rachtanapun 《应用聚合物科学杂志》2016,133(17)
Antibacterial polyethylene (PE)/silver nanoparticle (AgNP) nanocomposites containing AgNPs at concentrations of 5 × 10?5, 5 × 10?4, and 5 × 10?3 wt % were fabricated and tested. Transmission electron microscopy revealed an even dispersion of surface AgNPs in the PE/AgNP nanocomposites. No AgNP agglomeration was observed. The tensile strength, elongation at break, and Young's modulus of these PE/AgNP nanocomposites were similar to those of neat PE. Differential scanning calorimetry demonstrated that the PE/AgNP nanocomposites and neat PE had similar melting and crystallization temperatures of 126 ± 0.5 and 109 ± 0.6°C, respectively. The heats of fusion of the PE/AgNP nanocomposites containing AgNPs at concentrations of 5 × 10?5 and 5 × 10?4 and of 5 × 10?3 wt % were lower than those of neat PE by 5 and 7%, respectively. These PE/AgNP nanocomposites were immersed in shaking liquid cultures of the potential pathogenic bacteria Escherichia coli, Bacillus subtilis, and Salmonella typhimurium in the lag phase. The results show that the growth rates of all of the tested bacteria were restricted effectively after 1.5, 3, and 6 h of cultivation, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43331. 相似文献
108.
Ajit Sharma Doan Van Thuan Thanh-Dong Pham Mai Hung Thanh Tung Nguyen Thi Thanh Truc Dai-Viet N. Vo 《化学工程与技术》2020,43(4):752-761
FeO-doped TiO2 nanoparticle photocatalysts were immobilized onto the surface of fibrous activated carbon (ACF) via a sol-gel process. As an adsorbent and photocatalyst, FeO-TiO2 on immobilized ACFs (FeO-TiO2/ACF) greatly improved the photocatalysis rate of hydrogen production as compared with pure TiO2 and ACF-TiO2 under UV irradiation and visible light. The addition of ACFs surface significantly reduced the photogenerated pairs of electrons-hole recombination, thereby promoting the photocatalysis action of doped photo-metal oxides of FeO-TiO2. Co-doping of FeO onto the lattice of the TiO2 approach can improve the absorption activity of visible light through photo-metal oxide of TiO2 and further enhance hydrogen production under visible light. The photocatalytic fabrics (FeO-TiO2/ACF) were effortlessly split out from the experimental solution for re-utilization and exhibited high stability even after five complete regeneration cycles. 相似文献
109.
Hung‐Ming Yang Ch'un‐Min Wu Huai‐En Wu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2000,75(5):387-393
The kinetics of phase‐transfer catalyzed etherification of sodium phenoxide with ethyl 2‐bromoisobutyrate to produce ethyl 2‐phenoxyisobutyrate in a solid–liquid system has been investigated. Being catalyzed by the quaternary ‘onium salts, the reaction was carried out in a stirred batch reactor to explore the effects of various operating variables. At a temperature of 80 °C and a molar ratio of tetra‐n‐butylammonium bromide to sodium phenoxide equal to 0.372, 94% conversion was obtained after 4 h, and no other side products were observed. A kinetic model of pseudo‐first‐order reaction accompanied by catalyst deactivation was proposed to describe the overall reaction. A deactivation function was employed to evaluate the kinetic parameters. The decay of catalytic activity was mainly caused by the deposition of the salts produced on the surface of solid particles. The results show that the initial reaction rate was not influenced by the agitation rate when exceeding 350 rpm, but the deactivation rate increased with increasing stirring speed and the amount of catalyst used. The intrinsic organic reaction was conducted by the phase‐transfer catalytic intermediate. The order of reactivity for different phase‐transfer catalysts was determined as tetra‐n‐butylphosphonium bromide > tetra‐n‐butylammonium bromide > tetra‐n‐butylammonium iodide ≈ tetra‐n‐butylammonium hydrogen sulfate ≈ Aliquat 336. The apparent activation energy for tetra‐n‐butylammonium bromide was estimated as 51.4 kJ mol−1. This work provides an improved method for synthesizing phenolic substances in solid–liquid phases and preventing unfavorable side reactions. © 2000 Society of Chemical Industry 相似文献
110.
Hung C. Ling Man F. Yan Warren W. Rhodes 《Journal of the American Ceramic Society》1991,74(2):287-289
The aging behavior of a series of lead perovskite dielectrics with the compositions x Pb(Fe2/3 W1/3 )O3 ·(1 – x )Pb(Fe1/2 -Nb1/2 )O3 , where 0 ≤ x ≤ 1, and the effect of dopants were studied. Below the Curie temperature ( T c ), the capacitance and the dissipation factor (tan δ) decrease approximately linearly with logarithmic time. The aging rate depends on the temperature difference, Δ T , between the aging temperature and T c , and on the dopant concentration, but is independent of the measurement frequency between 1 and 1000 kHz. The maximum aging rate is about 3% per decade of time for capacitance and 5% per decade for tan δ at 1 mol% dopant concentration, and increases to 6.3% for capacitance and 8.5% for tan δ at 0.7 mol% dopant concentration. These results are consistent with an aging mechanism caused by changing ferroelectric domain structure with time, as proposed for BaTiO3 . 相似文献